Low
Flashing 40 on Heatline Capriz 25/28

Your boiler is struggling to work out the outside temperature because there is a problem with the external sensor or its wiring.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Fault on Outdoor sensor

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F0View →F5View →

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